Global Conflict

Long story short: it's a puzzle game based on chemistry in which you have to create compounds using "waldos", that are your only mean of interacting with the game. The fact is, you can't control them in real time, but you can give them a predefined set of instructions so they can create the compound you need X times, so usually need to create a loop. Now, I'm terribad at explaining, so go on the site, Here, and download the demo. It starts easy, it gets hard as the fuckin' hell, but everytime you manage to create that loop you need, when you see your waldos do all the friggin' work for you the sensation of accomplishment you feel is HUGE.
If you played The Codex of Alchemical Engineering (The flash game, which I strongly reccomend too), this game is pretty similar.
Oh, and btw, you don't actually need to know Chemistry, of course.
But really, try it, it's awesome, especially for those of you already used to this kind of logical thinking (Programmers, I suppose).

THIS GAME IS AWESOME!!!! Had it for a while and it's brain funk. That rush you get when you work out a puzzle. @.@

Its a great game, I played the demo long time ago.
Sadly I dont have the time (and the patience) to play it.
Actually I studied chemistry... and it is of no help at all!

I played a bit, but i kinda lost interest a the multiple-reactor stage...